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The article presents a study to see whether European Starlings (Sturnus vulgaris) and House Sparrows (Passer domesticus), common passerine birds associated with domestic animal production facilities, has a potential risk of pathogen transmission between facilities. It inoculated the species with 3 non-avian influenza virus strains consisting of swine H1N1 and H3N2 and Pandemic 2009 H1N1. It showed that the two species pose a negligible risk for transmission between swine production facilities.

Abstract: Maternally-derived yolk androgens influence the development and long-term phenotype of offspring in oviparous species. Between-female variation in the amounts of these yolk androgens has been associated with a number of social and environmental factors, suggesting that the variation is adaptive, but the mechanisms behind it are unknown. Using two different approaches, we tested the hypothesis that variation in yolk androgen levels across individuals is associated with variation in their capacity to synthesize androgens. First, we injected female house sparrows with exogenous gonadotropin-releasing hormone (GnRH) to maximally stimulate ovarian steroidogenesis. Second, we collected pre-ovulatory follicle tissue and quantified the mRNA expression of four key enzymes of the steroid synthesis pathway: steroidogenic acute regulatory protein (StAR), cytochrome P450-side chain cleavage enzyme (CYP11A1), 17β-hydroxysteroid dehydrogenase (HSD17B1), and aromatase (CYP19A1). Thirty minutes after GnRH injection, androgen concentrations in both the plasma and in the yolks of pre-ovulatory follicles were significantly elevated compared to controls. However, this measure of steroidogenic capacity did not explain variation in yolk testosterone levels, although physiological differences between house sparrows and more widely studied poultry models were revealed by this approach. Steroidogenic enzyme mRNA levels were detectable in all samples and were significantly lower in the most mature pre-ovulatory follicles. Of the four measured genes, CYP19A1 expression exhibited a significant negative relationship with yolk testosterone concentrations in laid eggs, revealing a key mechanism for between-female variation in yolk testosterone. Furthermore, this suggests that any factors which alter the expression of CYP19A1 within an individual female could have dramatic effects on offspring phenotype. [Copyright &y& Elsevier]

The article discusses a study that examined the susceptibility of sparrows and mice strains to Lawsonia (L.) intracellularis infection. Feces were collected and analyzed by polymerase chain reaction (PCR) for detection of the bacterial pathogen. The researchers found that none of the sparrows had any histologic lesions characteristic of proliferative enteropathy (PE) or antigen labeling by immunohistochemistry (IHC), while all the mice strains had histopathological lesions typical of PE and IHC labeling consistent with L. intracellularis infection.

Intensification of farming practices is a key factor in population declines of many species, including aerial insectivores. Of these species, Tree Swallow populations have been declining rapidly in Canada, likely in response to increased pesticide use (depleting insect prey) and destruction of marginal habitats (limiting cavity-nesting opportunities). Agricultural intensification may however be favourable to other species. House Sparrows for instance could benefit from abundant nesting sites (farm buildings) and food resources (grains) in intensive landscapes. Competition for nesting sites between these two species has been observed, and could be another factor in the decline of Tree Swallows. In a 400 nest-box study system embedded along a gradient of agricultural intensification of Southern Québec, Canada, we first assessed effects of intensification on abundance of House Sparrows by analysing 5,200 min of point counts. From these results, we modeled influence of competition and habitat on Tree Swallow nest site selection. Density of sparrows and proximity to buildings reduced the nest-box occupancy of swallows. Therefore, agricultural intensification had opposite influences on these two species, directly affecting House Sparrow abundance, but indirectly exacerbating competition pressure on swallows through competitor abundance. These results provide evidence of interspecific competition between these species, highlighting the indirect role of anthropogenic alterations on agro-ecosytems and illustrating a landscape-mediated avian competition pressure that has, to our knowledge, never been documented in farmscapes. [ABSTRACT FROM AUTHOR]

There are complex interactions between an organism's microbiome and its response to stressors, often referred to as the 'gut-brain axis'; however, the ecological relevance of this axis in wild animals remains poorly understood. Here, we used a chronic mild stress protocol to induce stress in wild-caught house sparrows (Passer domesticus), and compared microbial communities among stressed animals, those recovering from stress, captive controls (unstressed) and a group not brought into captivity. We assessed changes in microbial communities and abundance of shed microbes by culturing cloacal samples on multiple media to select for aerobic and anaerobic bacteria and fungi. We complemented this with cultivation-independent 16S and ITS rRNA gene amplification and sequencing, pairing these results with host physiological and immune metrics, including body mass change, relative spleen mass and plasma corticosterone concentrations. We found significant effects of stress and captivity on the house sparrow microbiomes, with stress leading to an increased relative abundance of endotoxin-producing bacteria - a possible mechanism for the hyperinflammatory response observed in captive avians. While we found evidence that the microbiome community partially recovers after stress cessation, animals may lose key taxa, and the abundance of endotoxin-producing bacteria persists. Our results suggest an overall link between chronic stress, host immune system and the microbiome, with the loss of potentially beneficial taxa (e.g. lactic acid bacteria), and an increase in endotoxin-producing bacteria due to stress and captivity. Ultimately, consideration of the host's microbiome may be useful when evaluating the impact of stressors on individual and population health., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)

Two adaptationist hypotheses have been proposed to explain why stress, particularly elevation of stress hormones (i.e. glucocorticoids), tends to suppress immune functions. One is that immune suppression represents efforts to minimize autoimmune responses to self-antigens released as organisms cope with stressors (i.e. the autoimmune-avoidance hypothesis). The other is that immune suppression occurs to promote a shunting of resources to life processes more conducive to survival of the stressor (i.e. the re-allocation hypothesis). Here In wild-caught house sparrows (Passer domesticus), we tested the second hypothesis, asking whether sustained elevation of baseline glucocorticoids, due to captivity, caused a greater rate of decline in immune functions than flight performance. A greater decline in immune functions than flight performance would support the re-allocation hypothesis. As in previous studies, we found that captivity tended to alter baseline corticosterone, suggesting that house sparrows experience captivity as a stressor. Captivity also affected several constitutive and induced innate immune metrics: bacterial (Escherichia coli) killing activity of blood and oxidative burst of leukocytes both changed in a manner consistent with immune disregulation. In contrast, breast muscle size and vertical flight (hovering) duration improved over captivity. Collectively, these changes provide indirect support for the re-allocation hypothesis, although within individuals, changes in immune and physical performance were unrelated. [ABSTRACT FROM AUTHOR]

The article presents a study on the occurrence of Salmonella species (spp.) and Escherichia (E.) coli in the feces samples of sparrows. The study also seeks to determine the pathogenicity, cytotoxicity and sensitivity profile of the isolates to antimicrobial use. It notes that E. coli infections in the industrial poultry breeding sector leads to a diversity of diseases and severe economic losses while Salmonella infections can cause acute and/or chronic diseases to affected animals. Samples from 228 sparrows have been examined, 30 of which tested positive for E. coli infection, five were resistant to antibiotics and one was positive for Salmonella infection.

We recorded the responses of free-ranging house sparrows (Passer domesticus) to various concentrations of primary repellents and a secondary repellent. Wheat treated with either lime or neem oil was consumed by sparrows at the same rate over 24 hours as plain wheat at all doses. d-pulegone significantly reduced wheat consumption from day 1 onwards throughout the 4 days. Avex™ (containing the secondary repellent anthraquinone) did not significantly reduce wheat consumption on day 1 of exposure, but sparrows ate progressively less repellent wheat over the following days. For both d-pulegone and Avex™, there was a negative relationship between wheat consumption and repellent concentration. In experiment 2, the highest concentrations of Avex™ + d-pulegone combined reduced daily wheat consumption significantly more than Avex™ alone and the effect lasted throughout the 10-day test. These results demonstrate the potential of primary and secondary repellents, presented alone or in combination, for modifying the feeding behaviour of sparrows. [ABSTRACT FROM AUTHOR]

BACKGROUND: Repellents may prevent bird pests from eating crops or protect non-target birds from eating harmful substances. The feeding behaviour of free-ranging house sparrows ( Passer domesticus) presented with wheat treated with the secondary repellent anthraquinone (AQ), paired with visual and/or olfactory and taste cues, was recorded in a series of trials. The aim was to determine the suitability of repellent combinations for preventing birds from consuming pest baits. RESULTS: Anthraquinone significantly reduced wheat consumption. The addition of cinnamon oil did not reduce consumption further, but the addition of either a blue colour or d-pulegone enhanced repellency. Green wheat was consumed more than blue wheat. In a multichoice test, the sparrows did not differentiate between low and high concentrations of AQ on blue-dyed wheat. With treatments on separate tables, the higher concentration was more repellent. Additional olfactory/gustatory cues palatable to pest mammals did not make the AQ-treated wheat more or less acceptable to sparrows. AQ-treated blue wheat with/without cinnamon oil was more repellent than green wheat with cinnamon oil, a colour/odour combination typically used for pest baits in New Zealand. CONCLUSIONS: These data demonstrate the potential of combining the secondary repellent AQ with additional salient cues for modifying the feeding behaviour of sparrows. Copyright © 2011 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Dependent offspring use specialized traits to attract parental care. In birds, this includes morphological ornaments (e.g. colourful plumage or mouthparts) that are associated with nestling condition and shape the allocation of parental care. Ornament expression often differs among broods, even after differences in individual condition are accounted for statistically. Understanding how this variation arises is important for understanding the information content of these signals, their functional importance, and their evolution. The present study used a cross-fostering experiment to assess the relative contributions of parental effects to among-brood differences in the mouth coloration of nestling house sparrows, specifically the carotenoid-richness, overall brightness, and ultraviolet (UV) coloration of rictal flanges. The expression of carotenoid-based coloration was explained by synchronous breeding, nest-of-rearing and nest-of-origin. Brightness and relative UV intensity, however, were explained only by synchronous breeding, and there was substantial unexplained variation in all three colour parameters. Among-brood variation in mouth coloration, then, may primarily contain information about the environment in which offspring are reared. At the individual level, ontogenetic changes in the carotenoid-richness and brightness of flanges positively reflected mass gain (a proxy for food intake). Larger and yellower chicks gained more mass, consistent with parental preferences for these traits. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 106, 169-179. [ABSTRACT FROM AUTHOR]

Potential mechanistic mediators of Darwinian fitness, such as stress hormones or sex hormones, have been the focus of many studies. An inverse relationship between fitness and stress or sex hormone concentrations has been widely assumed, although empirical evidence is scarce. Feathers gradually accumulate hormones during their growth and provide a novel way to measure hormone concentrations integrated over time. Using liquid chromatography–tandem mass spectrometry, we measured testosterone, corticosterone and cortisol in the feathers of house sparrows (Passer domesticus) in a wild population which is the subject of a long-term study. Although corticosterone is considered the dominant avian glucocorticoid, we unambiguously identified cortisol in feathers. In addition, we found that feathers grown during the post-nuptial moult in autumn contained testosterone, corticosterone and cortisol levels that were significantly higher in birds that subsequently died over the following winter than in birds that survived. Thus, feather steroids are candidate prospective biomarkers to predict the future survival of individuals in the wild. [ABSTRACT FROM AUTHOR]

Males frequently signal their resistance against parasites by elaborate ornaments. By mating with more ornamented males, females may choose less parasitized partners, and benefit by reducing the probability of contagion of parasites with direct transmission. Chewing lice (order Phthiraptera) are parasites of birds that considerably harm hosts, even decreasing survival. Previous studies showed that male house sparrows (Passer domesticus) can signal resistance against chewing lice by the size of the white wing bar, with more resistant birds having a larger bar. Here, in a mate-choice experiment, 16 female sparrows were presented to 16 dyads of males having similar initial wing bar sizes. In each dyad, the wing bar was experimentally reduced in a randomly selected male. Female house sparrows chose males with larger wing bars. Nevertheless, females also preferred males with less feather holes caused by chewing lice and larger males. By choosing males with larger wing bars, females choose males with larger uropygial glands, an organ involved in the resistance against chewing lice in this species. Therefore, white patches, which are widespread in birds, might be used by females in order to evaluate male resistance against chewing lice. [ABSTRACT FROM PUBLISHER]

The article discusses human approach and actions effect on bird's behavior in urban areas. It is revealed that discouraging behavior like keeping away birds influence bird flight initiation distances, indicating longer flight distance in places with high rate of discouraging actions. According to studies, citizens of Seattle, Washington discouraged birds more than the citizens of Berlin, Germany, while Berlin residents encouraged birds by offering more bird feeders than Seattle residents.

The article examines the seasonal variation and age-related correlates of Buggy Creek virus (BCV) Togaviridae infection in nestling house sparrows in Western Nebraska from 2006-08. Results showed no significant difference in the prevalence of BCV between years for sites sampled in two different seasons. The researchers observed a decline in average viremia titers with age and determined the length of viremia for nestlings in the field.

Abstract: Improved winter cold tolerance is widespread among small passerines resident in cold climates and is generally associated with elevated summit metabolic rate (M sum =maximum thermoregulatory metabolic rate) and improved shivering endurance with increased reliance on lipids as fuel. Elevated M sum and improved cold tolerance may result from greater metabolic intensity, due to mass-specific increase in oxidative enzyme capacity, or increase in the masses of thermogenic tissues. To examine the mechanisms underlying winter increases in M sum , we investigated seasonal changes in mass-specific and total activities of the key aerobic enzymes citrate synthase (CS) and β-hydroxyacyl CoA-dehydrogenase (HOAD) in pectoralis, supracoracoideus and mixed leg muscles of three resident passerine species, black-capped chickadee (Poecile atricapillus), house sparrow (Passer domesticus), and white-breasted nuthatch (Sitta carolinensis). Activities of CS were generally higher in winter than in summer muscles for chickadees and house sparrows, but not nuthatches. Mass-specific HOAD activity was significantly elevated in winter relative to summer in all muscles for chickadees, but did not vary significantly with season for sparrows or nuthatches, except for sparrow leg muscle. These results suggest that modulation of substrate flux and cellular aerobic capacity in muscle contribute to seasonal metabolic flexibility in some species and tissues, but such changes play varying roles among small passerines resident in cold climates. [Copyright &y& Elsevier]

Bioindicators are useful for environmental monitoring in ecosystems with pollution loads. We compared concentrations of selected 10 metals in 42 samples of House Sparrow in a polluted by thermal power plant and reference sites. We found mean tissue concentrations of some metals to be significantly higher in sparrows from the polluted area when compared to tissues from the reference site. In liver mean concentrations of Cu (35.85 ± 17.22 mg kg) and Zn (101.76 ± 26.38 mg kg) were significantly higher and concentration of Ni (0.43 ± 0.49 mg kg) were significantly lower in sparrows from the polluted area ( p < 0.05). The concentration of Cu was significantly higher in muscle and liver at the polluted site. Gender did not seem to influence residue levels, of the elements studied, among sparrows with the exception of kidney cobalt concentrations; which were higher in female sparrows than in males ( p < 0.05, t = −2.409). [ABSTRACT FROM AUTHOR]

Most host species of obligate interspecific brood parasites are under strong selection because such parasitism, e.g., that involving evictor nestmates, is highly costly. Egg rejection is one of the most efficient host defences against avian brood parasites. Many hosts have thus evolved egg-recognition ability and rejection behaviour. However, this defensive mechanism has not evolved in most species where only intraspecific brood parasitism occurs, probably because (1) the eggs of conspecific females are very similar in appearance, making egg rejection less likely to emerge, and (2) such parasitism is frequently less costly than interspecific parasitism. Using a captive population of house sparrows ( Passer domesticus) with a low breeding density, we here provide new evidence showing that this species actually has a fine capacity to discriminate conspecific eggs and to eject them (44.2% of foreign eggs ejected) while incurring very low rejection costs (4.2% of own eggs ejected). This result contradicts those previously found in high-density house sparrow populations in which very high rejection costs and very high clutch desertion rates were reported, probably as a consequence of intraspecific competition and infanticide provoked by the high breeding density. The house sparrow has only rarely been reported as the host of an interspecific brood parasite, which implies that it is a newly described example of an altricial species in which egg ejection has evolved and is maintained in response to intraspecific brood parasitism. [ABSTRACT FROM AUTHOR]

Immunity is necessary in order to fight parasites and pathogens, but immune protection also incurs a cost for the hosts. Therefore, immunity should be traded against other fitness-related traits. Body mass, as a function of body reserves, is important in birds of temperate zones during winter. Sedentary temperate birds usually increase body mass just before winter to survive a period with low food availability and thermoregulatory requirements. Given that immunity is costly and affects body mass, a trade-off is predicted between body mass and immunity in wintering birds. Such a trade-off was tested experimentally by stimulating the immune system of a group of wintering house sparrows ( Passer domesticus) from a Spanish population in an outdoor aviary with a lipopolysaccharide while another group served as control. The activation of the immune system negatively affected body mass, despite the relatively mild temperatures of the study zone. Such a trade-off between body mass and immunity was found in other similar studies during breeding, but not during moult, suggesting that the trade-off between immunity and body mass may vary seasonally. [ABSTRACT FROM AUTHOR]

Life history theory predicts that individuals should maximize their fitness by balancing current investment in offspring versus future prospects for reproduction. Faced with reduction of their current clutch, birds should desert if the prospective opportunity would increase inclusive fitness more than continued investment in the reduced clutch. I studied nest desertion in response to clutch reduction by house sparrows (Passer domesticus) to determine if continuing investment in a reduced clutch differs based on proportion of original clutch remaining, stage in incubation, and ordinal date. Nests were reduced to two eggs early or late in incubation over two complete breeding seasons. Of 150 nests manipulated, 36 were deserted. Nests were more likely to be deserted when reduction occurred earlier in incubation, earlier in the season, and with a smaller proportion of original clutch remaining. This suggests that both time and brood size are used to assess the tradeoffs between current and future investment. However, near the end of the breeding season, the proportion of original clutch remaining and stage in incubation were less important, and low desertion was likely associated with a lack of re-nesting opportunities in the current season. Therefore, whether to desert or continue investing in a reduced clutch is a function of offspring reproductive value (RV) when there is opportunity for re-nesting in the same season. However, near the end of the season the decision is based on the residual reproductive value (RRV) of parents. [ABSTRACT FROM AUTHOR]

The article describes the histologic and immunohistochemical characteristics of the host response in systemic isosprosis Atoxoplasmosis in a colony of captive American goldfinches Spinus tristis and house sparrows Passer domesticus. Histological results revealed severe lesions in the proximal small intestines and histological changes showed infiltraes of lymphocytes, and atypical cells. Immunohistochemical findings suggest T-cell lymphoma.

Hormones mediate major physiological and behavioural components of the reproductive phenotype of individuals. To understand basic evolutionary processes in the hormonal regulation of reproductive traits, we need to know whether, and during which reproductive phases, individual variation in hormone concentrations relates to fitness in natural populations. We related circulating concentrations of prolactin and corticosterone to parental behaviour and reproductive success during both the pre-breeding and the chick-rearing stages in both individuals of pairs of free-living house sparrows, Passer domesticus. Prolactin and baseline corticosterone concentrations in pre-breeding females, and prolactin concentrations in prebreeding males, predicted total number of fledglings. When the strong effect of lay date on total fledgling number was corrected for, only pre-breeding baseline corticosterone, but not prolactin, was negatively correlated with the reproductive success of females. During the breeding season, nestling provisioning rates of both sexes were negatively correlated with stress-induced corticosterone levels. Lastly, individuals of both sexes with low baseline corticosterone before and high baseline corticosterone during breeding raised the most offspring, suggesting that either the plasticity of this trait contributes to reproductive success or that high parental effort leads to increased hormone concentrations. Thus hormone concentrations both before and during breeding, as well as their seasonal dynamics, predict reproductive success, suggesting that individual variation in absolute concentrations and in plasticity is functionally significant, and, if heritable, may be a target of selection. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the relationship of carotenoid-based mouth coloration in nestling House Sparrows. It reveals a positive relationship between carotenoid concentration and the intensity of yellow coloration and the presence of carotenoids in rictal flanges. Furthermore, it indicates a positive association of carotenoid-based coloration with nestling mass and with plasma carotenoid concentration.

The article presents a study concerning the decline of populations of House Sparrow in eastern North America, as a result of competition between the House Finch and the House Sparrow. It examines the evidence of competition at a local aspect during the breeding season by assessing patterns of co-occurrence of the two birds. Moreover, it notes that decrease of populations within the southeastern U.S. was not associated with House Fince abundance.

The article discusses a study completed in 2010 regarding how House Sparrows, Passer domesticus in Latin, deal with parasitic infection. It states that while literature exists on the effects of infection in Domestic Chickens, Gallus gallus domesticus in Latin, little is known about how they affect the passerine species. It reports that researchers compared the humoral immune responses of both captive House Sparrows with those in the wild, also looking into their egg yolks, and found that both had mite-specific antibodies to deal with infection.

Despite rapidly accumulating evidence for the existence of consistent individual differences in suites of correlated behaviours (i.e. ‘animal personalities’), little is known about proximate mechanisms causing such variation. Individual variation in circulating levels of testosterone (T) is often hypothesized to underpin personality traits such as aggressiveness and exploratory behaviour. Here we provide a comprehensive test of this hypothesis. We quantified variation in exploratory behaviour of a novel environment in a captive population of wild-caught male house sparrows, Passer domesticus. We then investigated the relationship between the observed behaviours and circulating levels of T, using two approaches. First, we tested whether measures of exploratory behaviour correlated with (1) point-sampled plasma T levels and (2) T-dependent ornamentation (bill coloration) in 114 males. Neither direct nor indirect estimates of individual variation in T levels were correlated with the assayed behaviours. Second, we experimentally increased plasma T levels of 21 males with T implants, using 21 placebo-implanted males as a control group. Experimentally induced between-individual variation in T levels did not increase the amount of between-individual variation in exploratory behaviour. Our results thus strongly suggest that, in house sparrows, between-individual variation in circulating levels of T cannot serve as a causal explanation for the existence of individual variation in exploratory behaviour. [ABSTRACT FROM AUTHOR]

Abstract: Small random deviations from left–right symmetry in bilateral traits, termed fluctuating asymmetry (FA), are theoretically predicted to increase with environmental stress and believed to constitute a potential biomarker in conservation. However, reported relationships between FA and stress are generally weak and variable among organisms, traits and stresses. Here we test if, and to what extent, FA increases with nutritional stress, estimated from independent feather growth measurements, in free-ranging house sparrows (Passer domesticus). Ptilochronological feather marks showed significant heterogeneity among study plots, indicating that house sparrow populations were exposed to variable levels of nutritional stress during development. However, individuals from more stressed populations did not show increased levels of fluctuating asymmetry in tarsus or rectrix length, nor was there evidence for significant between-trait concordance in FA at the individual or the population level. Lack of support for FA in tarsus and rectrix length as estimator of nutritional stress in house sparrows may indicate that developmental instability is insensitive to nutritional stress in this species, poorly reflected in patterns of fluctuating asymmetry due to ecological or statistical reasons, or highly context-specific. Such uncertainty continues to hamper the use of FA as a biomarker tool in conservation planning. [ABSTRACT FROM AUTHOR]

Individuals respond differently to stressors and it has been suggested that stress responses are related to coping styles (consistent individual differences in behavior and physiology). We studied behavioral responses to a novel object and corticosterone response to stress during chick rearing in free-living female house sparrows (Passer domesticus). To prevent mates from influencing each others' behavior, we removed the males temporarily from nests and tested the females the following day either with a novel object placed on the nest box or as control. The two groups differed only in behaviors that were a priori defined as responses to the novel object (latency to first feeding, time spent near the nest, and inspecting the novel object by hovering in front of it) indicating that mate-removal per se had no effect on female behavior. Based on these variables, females' coping behaviors were categorized as 'bold', 'inquisitive' or 'shy' by discriminant analysis. Baseline corticosterone, measured on the day following the novel-object or control test, was not related to any measure of coping. Stress-induced corticosterone, however, was negatively related to number of hoverings in front of the nest (a measure of explorativeness) and accordingly differed between the behavioral coping categories, with 'inquisitive' birds having the lowest stress response. We propose that the relationship between physiological stress response and behavioral response to novelty (a component of personality or coping style) may be more complex than previously suggested, and individuals cannot always be unambiguously categorized along a single personality axis. [ABSTRACT FROM AUTHOR]

Abstract: The steroid hormone testosterone (T) plays a central role in the regulation of reproduction in animals. Although seasonal variation in T levels is well-studied, differences between day and night have only been described in relatively few species, and daily within-individual variation has been largely neglected when evaluating the relationship between T and the expression of sexual ornaments or behavior. We measured plasma T levels during day and night in a captive population of House Sparrows, and analyzed their relationship with an important male ornament – badge size. T levels were on average twice as high at night than during daytime. This was true in all seasons, and in both males and females. Disturbance of the birds at night, but not during the day, led to significantly lower T levels, suggesting a rapid drop after an individual wakes up. The relationship between T levels and badge size depended on the time when T was measured. During the breeding season, badge size was strongly positively correlated with night-time, but not with daytime T levels. This suggests that badge size signals information related to an individual’s maximum potential T level such as social dominance. Our study highlights that integrative research on the endocrine control of ornament expression needs to take diel variation in hormone levels into account. [ABSTRACT FROM AUTHOR]

Differences in the survival rates of males and females over the period from hatching to recruitment can have important impacts on individual fitness and population demographics. However, whilst the influence of an individual's sex on nestling growth and survival has been well studied, less is known about sex-specific survival over the period between fledging and recruitment. Here, we analyse nestling survival and recruitment in an isolated, island population of house sparrows ( Passer domesticus), using data collected over a 4-year period. Nestlings that had a greater mass at 1 day old were more likely to fledge. Recruitment was also positively associated with day 11 mass. The positive influence of nestling mass on survival to fledging also increased as brood size increased. There was no difference in the survival of male and female individuals prior to fledging. In contrast, over the period from fledging to recruitment, females had significantly less mortality than males. Recruitment was also positively associated with 11-day-old mass. Neither the nestling sex ratio nor the fledging sex ratio deviated from 0.5, but the sex ratio amongst recruits was female biased. Our study shows that sex can influence juvenile survival, but also shows that its effect varies between different life-history stages; therefore, these stages should be considered separately if we want to understand at what point sex-specific differences in juvenile survival occur. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101, 680-688. [ABSTRACT FROM AUTHOR]

Abstract: The central life-history trade-off between current and future reproductive effort seems to be mediated by corticosterone in birds. However, still little is known about how naturally occurring corticosterone levels during an acute stress may influence subsequent parental behavior. In this study we observed the parental behavior of free-living male house sparrows (Passer domesticus) both before and after they were subjected to a standard capture–handling stress. We investigated the relationships between corticosterone levels, pre- and post-stress parental behavior, while we statistically controlled for a number of other variables using a multivariate regression method, the path analysis. We found that males'' baseline feeding rate predicted the body mass of the nestlings, indicating that male parental care is directly linked to fitness. Corticosterone levels were not explained by baseline feeding rate, but both baseline and stress-induced corticosterone levels had a negative influence on the males'' post-stress feeding behavior. Moreover, males with large bib size had a stronger stress response and lower post-stress feeding rate than small bibbed males. These results indicate that naturally occurring variation in baseline and stress-induced corticosterone levels may influence subsequent parental decisions: individuals mounting a robust stress response are likely to reduce their parental commitment. Parental effort may be regulated in a complex manner, with corticosterone mediating the life-history trade-off between current reproduction and survival. However, different resolutions of this trade-off were apparent only following the stress, therefore the ability to modulate the stress response and maintain parental care in stressful situations may be important in life-history evolution. [Copyright &y& Elsevier]

Difference between sexes in parasitism is a common phenomenon among birds, which may be related to differences between males and females in their investment into immune functions or as a consequence of differential exposure to parasites. Because life-history strategies change sex specifically during the annual cycle, immunological responses of the host aiming to reduce the impact of parasites may be sexually dimorphic. Despite the great complexity of the immune system, studies on immunoecology generally characterise the immune status through a few variables, often overlooking potentially important seasonal and gender effects. However, because of the differences in physiological and defence mechanisms among different arms of the immune system, we expect divergent responses of immune components to environmental seasonality. In male and female house sparrows ( Passer domesticus), we measured the major components of the immune system (innate, acquired, cellular and humoral) during four important life-history stages across the year: (1) mating, (2) breeding, (3) moulting and (4) during the winter capture and also following introduction to captivity in aviary. Different individuals were sampled from the same population during the four life cycle stages. We found that three out of eight immune variables showed a significant life cycle stage × sex interaction. The difference in immune response between the sexes was significant in five immune variables during the mating stage, when females had consistently stronger immune function than males, while variables varied generally non-significantly with sex during the remaining three life cycle stages. Our results show that the immune system is highly variable between life cycle stages and sexes, highlighting the potential fine tuning of the immune system to specific physiological states and environmental conditions. [ABSTRACT FROM AUTHOR]

Parental effort has a direct impact on individual fitness. Theoretical models exploring how parental effort evolves to cope with offspring demand and sexual conflicts may differ in the assumptions they make in respect to the genetic heritability of parental behaviours. Only a few attempts, however, have been made to estimate the heritability of parental behaviours and their possible co-evolution with offspring solicitation behaviour. Analysing parent and offspring behaviours in four generations of cross-fostered broods of house sparrows, we found that parental effort (food delivery rate) was repeatable across consecutive broods and heritable across generations. In contrast, parental response to experimentally induced changes in nestling begging was neither repeatable across broods nor heritable across generations or correlated to nestling begging. Thus, the results give no indication for genetic covariance between begging intensity and parental response, but provide the first cross-fostering-based evidence for the heritability of parental investment levels across generations. [ABSTRACT FROM AUTHOR]

The article discusses a study to determine how dietary calcium affects bird plumage. It states that the colors of their feathers are the result of how melanin is processed in their bodies. The researchers selected young male House Sparrows who were given different diets with varying degrees of calcium, low, medium and high. A control group was given a diet of bicarbonate with even less calcium than the group given low amounts of it. Results showed that those on the low calcium diet benefited the most, which had no effect on their plumage.

This study was conducted on the campus of the regional department of the forestry service, encompassing 2.25 ha in Antalya city center. The area has gardens and is surrounded by trees, providing nesting and feeding opportunities for many songbird species. The study aimed to determine clutch and egg size variation, breeding success, and productivity of the House Sparrow (Passer domesticus), in terms of clutch size and breeding attempts, and to evaluate variation in temperature, rainfall, and humidity in terms of breeding attempts and years, and their possible effects on given parameters of the species. In total, 2016 eggs were laid in 393 clutches and clutch size varied from 1 to 11 eggs; the clutches most commonly contained 4-6 egg in the 3 consecutive years. Mean egg length, width, weight, volume, and sphericity index were 21.16 ± 0.03 mm, 14.99 ± 0.01 mm, 2.02 ± 0.01 g, 2.38 ± 0.01 cm3, and 71.01 ± 0.09, respectively. Breeding attempts were affected by temperature (r = 0.97 P < 0.0001) and rainfall (r = -0.84 P < 0.001). Egg length was affected by rainfall (r = 0.60 P < 0.041), humidity (r = 0.59 P < 0.044), and temperature (r = -0.81 P < 0.002), and egg volume was affected by temperature (r = -0.68 P < 0.015). This study shows that the House Sparrow population in the study area exhibited important variation in clutch and egg size, which was affected by changes in temperature, rainfall, and humidity. [ABSTRACT FROM AUTHOR]

The article discusses a study examining the predatory role of the Eurasian Sparrowhawk in the declining population of House Sparrow in Great Britain. Evidence of decline among prey species of sparrows has been reported in the data published by the Garden Bird Feeding Survey (GBFS) of the British Trust for Ornithology. Statistical information illustrating the differences in temporal trends in Eurasian Sparrowhawk incidence and House Sparrow population data between rural and urban sites studied are noted.

Sperm competition exerts strong selection on males to produce spermatozoa with an optimal morphology that maximizes their fertilization success. Long sperm were first suggested to be favored because they should swim faster. However, studies that investigated the relationship between sperm length and sperm competitive ability or sperm swimming velocity yielded contradictory results. More recently, ratios of the different sections of a spermatozoon (the head, midpiece, and flagellum) were suggested to be more crucial in determining swimming velocity. Additionally, sperm ability to remain and survive in the female storage organs may also influence fertilization success, so that optimal sperm morphology may rather maximize sperm longevity than velocity. In this study, we investigated how sperm morphology is related to sperm velocity and sperm longevity in the house sparrow Passer domesticus. Sperm velocity was found to be correlated with head/flagellum ratio. Sperm with small heads relative to their flagellum showed higher swimming velocity. Additionally, shorter sperm were found to live longer. Finally, we found sperm morphological traits to vary substantially within males and the head/flagellum ratio to be unrelated to total sperm length. We discuss the hypothesis that the substantial within-male variation in sperm morphology reflects a male strategy to produce a diversity of sperm from long, fast-swimming to short, long-living sperm to maximize their fertilization success in a context of sperm competition. [ABSTRACT FROM AUTHOR]

Abstract: Toxoplasma gondii is a cosmopolitan protozoan parasite of warm-blooded animals that causes high rates of infection in mammals and birds. Sparrows (Passer domesticus) are synantropic birds which are distributed worldwide. They serve as intermediate hosts for the parasite but are quite resistant to toxoplasmosis. The aims of this study were to determine the frequency of T. gondii infection in sparrows using serologic and molecular tests, and to investigate related parasites, such as Neospora caninum and Hammondia sp., using a nested PCR for Toxoplasmatinae DNA followed by sequence analysis of the PCR amplicons. A total of 293 sparrows were trapped at the states of Bahia and Pernambuco, Brazil. Tissues of 40 animals were available for molecular tests. Antibodies to T. gondii were found in 1.02% (3/293) of animals using a hemagglutination test, with titers ranging from 1:32 to 1:128. Toxoplasmatinae DNA was detected in 10/40 (25%) sparrows; after nucleotide sequencing, T. gondii was confirmed in 7/40 (17.5%) birds and N. caninum in 3/40 (7.5%) animals. Sparrows from Brazil were confirmed as intermediate hosts of T. gondii, that reinforces the potential importance of these birds on the transmission of the parasite to cats and other animals that may predate sparrows. In addition, N. caninum was detected for the first time in sparrows. To the authors’ knowledge, this is the first wild synantropic bird species identified as intermediate host of N. caninum. These findings seem to have a great epidemiologic impact because of the cosmopolitan distribution of sparrows and due to their increasing population in urban and rural areas. [Copyright &y& Elsevier]

Abstract: Many birds exhibit considerable phenotypic flexibility in metabolism to maintain thermoregulation or to conserve energy. This flexibility usually includes seasonal variation in metabolic rate. Seasonal changes in physiology and behavior of birds are considered to be a part of their adaptive strategy for survival and reproductive success. House Sparrows (Passer domesticus) are small passerines from Europe that have been successfully introduced to many parts of the world, and thus may be expected to exhibit high phenotypic flexibility in metabolic rate. Mass specific Resting Metabolic Rate (RMR) and Basal Metabolic Rate (BMR) were significantly higher in winter compared with summer, although there was no significant difference between body mass in summer and winter. A similar, narrow thermal neutral zone (25–28°C) was observed in both seasons. Winter elevation of metabolic rate in House Sparrows was presumably related to metabolic or morphological adjustments to meet the extra energy demands of cold winters. Overall, House Sparrows showed seasonal metabolic acclimatization similar to other temperate wintering passerines. The improved cold tolerance was associated with a significant increase in VO2 in winter relative to summer. In addition, some summer birds died at 5°C, whereas winter birds did not, further showing seasonal variation in cold tolerance. The increase in BMR of 120% in winter, compared to summer, is by far the highest recorded seasonal change so far in birds. [Copyright &y& Elsevier]

Predation cost (Pc) is often regarded as a pivotal component determining foraging behavior. We hypothesized that variations in two of its major constituents, predation risk (μ) and the marginal value of energy (∂Fs/∂e, where Fs is the survivor's fitness and e represents the amount of acquired energy), will translate into variations in patch use behavior of ground-foraging birds. We studied patch use behavior of House Sparrows (Passer domesticus), as affected by the proximity to shelter, in two large outdoor aviaries. Proximity to shelter should affect μ. We manipulated the birds' flight performance by clipping primary flight feathers from their wings to increase μ, but the clipping may also increase ∂Fs/∂e. To help distinguish between the birds' response to these confounding effects, we further augmented food in the aviaries to reduce ∂Fs/∂e. Patch use, as measured by giving-up densities (GUD, the amount of food left behind in a resource patch following exploitation) was affected by distance from shelter only slightly and mainly when the birds were feather-clipped and food was not augmented. Food augmentation had a homogenizing effect on foraging costs by increasing GUDs and washing out the effects of distance and feather clipping. We argue that t' increases with distance from shelter but that, for the highly urban House Sparrow, this increase is only slight. Feather clipping then increased μ further to the point at which patch use discernibly decreased with distance from shelter. Our experimental manipulation of feather clipping also acted to increase ∂Fs/∂e and resulted in an overall lowering of GUDs. The seed augmentation counteracted the effect of feather clipping on ∂Fs/∂e, allowing the birds to reduce their foraging efforts and washing out the qualitative effect of μ with respect to distance from shelter. [ABSTRACT FROM AUTHOR]

Brood parasitism could be a selective pressure on each female to have a type of egg that permits recognition. House sparrows ( Passer domesticus) undergo conspecific brood parasitism and can recognise parasitic eggs. In this study, we analyse the effect of relative size in experimental parasitic eggs compared to the host eggs. We modified egg colour and the spot pattern to determine the influence of these characteristics on egg rejection. Furthermore, we examine whether egg rejection increases with “stimulus summation”. Our results show that egg rejection is not affected by relative egg size. However, changes in the spot pattern proved to exert the highest influence on egg rejection (32.4% of trials), significantly higher than when only egg colour is changed (3.8%). Therefore, our results suggest that parasitism may be a pressure favouring the maintenance of spotted eggs in house sparrow. [ABSTRACT FROM AUTHOR]

When allocating investment among offspring, parents might maximize their fitness by biasing investment toward offspring with the best direct fitness prospects. The observed preferences of avian parents for carotenoid-rich mouth colors that advertise good condition has been interpreted as support for this hypothesis. However, because these condition-dependent visual signals might also make offspring more visually conspicuous, active parental preferences for carotenoid-rich traits are difficult to distinguish from passive responses to differences in detectability among offspring. Here, we used a visual model to examine how mouth colors influence the visual conspicuousness of nestling house sparrows ( Passer domesticus) to parents under a suite of realistic ambient light conditions. We found little evidence that mouths rich in carotenoids provided more conspicuous targets to parents than mouths poor in carotenoids. While other features of mouth color may have evolved to increase conspicuousness, our results suggest that carotenoid-based coloration is not a product of detectability pressures and rather may serve as a signal of nestling quality. [ABSTRACT FROM AUTHOR]

During winter 2015 in Montreal (Canada), we observed on two occasions a group of House Sparrows ( Passer domesticus) hiding under the body of several cars, in the empty spaces between the wheels and the fender. On both occasions, it was either snowing or raining. This paper reports for the first time, to our knowledge, a description of birds using cars to shelter from rain or snow. Moreover, some individuals were engaged in continuous round trips between the car and bushes, seemingly to detect potential predators that would not be visible to the individuals under the car. Further study should examine the diversity of foraging and non-foraging innovations in different groups of birds, in order to better understand the evolution of behavioral flexibility and cognition in non-human animals. [ABSTRACT FROM AUTHOR]

Songbirds exhibit seasonal plasticity in a broad variety of behavioral and morphological traits associated with reproduction. Changes in song production are well described while changes in song reception are not. In the present study, we test for seasonal variation in auditory processing of the house sparrow (Passer domesticus L.) using auditory brainstem responses (ABRs) to tone bursts. We measured amplitude and latency of the first ABA peak in spring, summer and autumn at stimulus frequencies from 0.8 to 6.4kHz and intensity levels from 24 to 80dB SPL. ABA thresholds were determined at each frequency using cross-correlation. Amplitude was greater in spring than in autumn at frequencies from 3.2 to 6.4kHz whereas latency and thresholds exhibited no seasonal variation. The results indicate an increase in the number or temporal synchrony of responses from peripheral auditory neurons during the early breeding season. Changes in peripheral auditory processing may enhance temporal coding of the fine structure and envelope of song; thereby, improving assessment of encoded information in both sexes (e.g. individual identity and dominance status) and auditory feedback during song production in males. Peripheral auditory changes may be mediated by reproductive hormones, and could involve changes in hair cell density on the basilar papilla. Our results suggest that peripheral auditory processing of songbirds changes seasonally in parallel with other behavioral and morphological traits, such as song production. [ABSTRACT FROM AUTHOR]

Most arthropod-borne viruses (arboviruses) show distinct serological subtypes or evolutionary lineages, with the evolution of different strains often assumed to reflect differences in ecological selection pressures. Buggy Creek virus (BCRV) is an unusual RNA virus (Togaviridae, Alphavirus) that is associated primarily with a cimicid swallow bug (Oeciacus vicarius) as its vector and the Cliff Swallow (Petrochelidon pyrrhonota) and the introduced House Sparrow (Passer domeslicus) as its amplifying hosts. There are two sympatric lineages of BCRV (lineages A and B) that differ from each other by >6% at the nucleotide level. Analysis of 385 BCRV isolates all collected from bug vectors at a study site in southwestern Nebraska, USA, showed that the lineages differed in their peak times of seasonal occurrence within a summer. Lineage A was more likely to be found at recently established colonies, at those in culverts (rather than on highway bridges), and at those with invasive House Sparrows, and in bugs on the outsides of nests. Genetic diversity of lineage A increased with bird colony size and at sites with House Sparrows, while that of lineage B decreased with colony size and was unaffected by House Sparrows. Lineage A was more cytopathic on mammalian cells than was lineage B. These two lineages have apparently diverged in their transmission dynamics, with lineage A possibly more dependent on birds and lineage B perhaps more a bug virus. The long-standing association between Cliff Swallows and BCRV may have selected for immunological resistance to the virus by swallows and thus promoted the evolution of the more bug-adapted lineage B. In contrast, the recent arrival of the introduced House Sparrow and its high competence as a BCRV amplifying host may be favoring the more bird-dependent lineage A. [ABSTRACT FROM AUTHOR]

In the present study, we experimentally manipulated coccidian parasitism and dietary carotenoid availability in a fully factorial experiment in male house sparrows (Passer domesticus Linnaeus), and tested whether carotenoid supplementation reduces the cost of parasitism in terms of condition, moult and immune responses. We found that coccidians have a significant but transient negative effect on body mass, which can be reduced if birds have access to carotenoid supplementation in their diet. Experimental manipulation had no significant effect on the moulting parameters of the birds measured following coccidian infestation and during the whole moulting period. Carotenoid supplementation increased the plasma carotenoid concentration in both infested and medicated birds treated with a coccidiostatic drug; however, after two months exposure to parasites, plasma carotenoid concentration increased only in the carotenoid-supplemented and medicated group whereas no difference was observed between the carotenoid-supplemented and infested and non-supplemented groups. On the contrary, coccidian infestation was not affected by carotenoid supplementation. Experimental infestation decreased the antibody response to sheep red blood cells (SRBCs), although no significant effect was observed in the capacity of the birds to respond to a mitogenic challenge with phytohemagglutinin. Within the experimentally infested groups birds with carotenoid-supplemented food tended to have an increased anti-SRBC humoral immune response. The positive correlation between coccidian infestation and the strength of the humoral immune response against SRBCs in the non-supplemented and infested groups indicates that this part of the immune system plays an important role in defence against these parasites. [ABSTRACT FROM AUTHOR]

The article discusses a study that aims to assess the sources of variation in the phenotypes of House Sparrows. A partial cross-foster design was used to investigate sources of variation in a component of immunity and three morphological traits in nestling sparrows. The authors note that date in season influenced most nestling traits. According to findings of the study, male sparrows demonstrated greater origin-related and less rearing-related variance in immune response compared to females.

Abstract: Non-aggressive social interactions between group-mates, e.g. maintenance of spatial proximity or activity synchrony are basic elements of a species’ social structure, and were found to be associated with important fitness consequences in group-living animals. In the establishment of such affiliative relationships, kinship has often been identified as one of the key predictors, but this has rarely been studied in simple social groups such as flocks of gregarious birds. In this study we investigated whether kinship affects social preference, as measured by the tendency to associate with others during various social activities, in captive house sparrow (Passer domesticus) flocks where birds could interact with differently related flock-mates. We found that preference between flock-mates was correlated with familiarity from early nestling period: same-brood siblings followed their sib initiating new activities more often than non-sib birds. The strength of association between birds also tended to correlate with genetic relatedness, but this was mainly due to the effect of siblings’ affiliation. Thus we concluded that house sparrows prefer the company of their siblings during social activities even well after fledging, which may facilitate kin-biased behaviours. [Copyright &y& Elsevier]